1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 #ifndef _UAPIS390_CMB_H
3 #define _UAPIS390_CMB_H
4
5 #include <linux/types.h>
6
7 /**
8 * struct cmbdata - channel measurement block data for user space
9 * @size: size of the stored data
10 * @elapsed_time: time since last sampling
11 * @ssch_rsch_count: number of ssch and rsch
12 * @sample_count: number of samples
13 * @device_connect_time: time of device connect
14 * @function_pending_time: time of function pending
15 * @device_disconnect_time: time of device disconnect
16 * @control_unit_queuing_time: time of control unit queuing
17 * @device_active_only_time: time of device active only
18 * @device_busy_time: time of device busy (ext. format)
19 * @initial_command_response_time: initial command response time (ext. format)
20 *
21 * All values are stored as 64 bit for simplicity, especially
22 * in 32 bit emulation mode. All time values are normalized to
23 * nanoseconds.
24 * Currently, two formats are known, which differ by the size of
25 * this structure, i.e. the last two members are only set when
26 * the extended channel measurement facility (first shipped in
27 * z990 machines) is activated.
28 * Potentially, more fields could be added, which would result in a
29 * new ioctl number.
30 */
31 struct cmbdata {
32 __u64 size;
33 __u64 elapsed_time;
34 /* basic and exended format: */
35 __u64 ssch_rsch_count;
36 __u64 sample_count;
37 __u64 device_connect_time;
38 __u64 function_pending_time;
39 __u64 device_disconnect_time;
40 __u64 control_unit_queuing_time;
41 __u64 device_active_only_time;
42 /* extended format only: */
43 __u64 device_busy_time;
44 __u64 initial_command_response_time;
45 };
46
47 /* enable channel measurement */
48 #define BIODASDCMFENABLE _IO(DASD_IOCTL_LETTER, 32)
49 /* enable channel measurement */
50 #define BIODASDCMFDISABLE _IO(DASD_IOCTL_LETTER, 33)
51 /* read channel measurement data */
52 #define BIODASDREADALLCMB _IOWR(DASD_IOCTL_LETTER, 33, struct cmbdata)
53
54 #endif /* _UAPIS390_CMB_H */